android - Is it possible to crop camera preview?

Question

I have not found any way to crop camera ppreview and then display it on the SurfaceView.

Android - Is it possible to crop camera preview?

Answer 1

You can do this without overlay views (which won't work in all situations).

Subclass ViewGroup, add the SurfaceView as the only child, then:

1. in onMeasure supply the cropped dimensions you want.
2. in onLayout, layout the SurfaceView with the un-cropped dimensions.

basically,

public class CroppedCameraPreview extends ViewGroup {
  private SurfaceView cameraPreview;
  public CroppedCameraPreview( Context context ) {
    super( context );
    // i'd probably create and add the SurfaceView here, but it doesn't matter
  }
  @Override
  protected void onMeasure( int widthMeasureSpec, int heightMeasureSpec ) {
    setMeasuredDimension( croppedWidth, croppedHeight );
  }
  @Override
  protected void onLayout( boolean changed, int l, int t, int r, int b ) {
    if ( cameraPreview != null ) {
      cameraPreview.layout( 0, 0, actualPreviewWidth, actualPreviewHeight );
    }
  }
}